Cables are frequently equipped with one or multiple inner (electrical) signal lines and a shield wire developed coaxially around these signal lines. The shield wire is supposed to reduce or entirely prevent electromagnetic influences on the signal line(s) so that interferences in the signal transmission through the signal line(s) can be reduced or avoided.
For better shielding, the shield wire may be connected in such a way that it is at ground potential. There may be situations, however, where the two ends of the cable are connected in such a way that the shield wire via the two ends is connected to different grounded connections. This may have the disadvantage that a connection of the shield wire to different ground potentials may result in a usually undesired flow of current (a so-called sheath current) across the shield wire, which may result in undesired effects and in a degradation of the shielding of the signal lines.
To avoid such a flow of current across the shield wire, different possibilities are known in the related art for decoupling (i.e. galvanic isolation) of the shield wire, for example sheath current filters, for which circuit boards having fitted discrete components may be used. Using these components, it is possible to interrupt the shield wire and reconnect it in accordance with the requirements in such a way that a flow of current in the shield wire may be prevented. The circuit board and the components required for this purpose may be installed in a housing and/or extrusion coated and/or embedded in the cables.
This usually requires considerable additional space, however. It may also be the case that some methods for running electrical lines cannot be used with such decoupling, for example a method of pulling electrical lines through, since the additional components for decoupling the shield wire are often significantly larger than the cross section of the cable and may resist being pulled through. Furthermore, these additional components usually require substantial procurement costs and increase the manufacturing effort required for the cable so that the manufacturing costs for the cable are increased.